The present invention relates to a plastisol composition that exhibits improved abrasion resistance when in the fused state.
A plastisol is a suspension of a vinyl chloride polymer in a liquid plasticizer for the vinyl chloride polymer. Vinyl chloride polymers used in plastisol formulations normally are referred to as vinyl chloride "paste resins" or "dispersion resins" and have a relatively small particle size. Commercially available vinyl chloride paste resins typically have an average particle size of from about 2 to 12 micrometers in diameter. Although homopolymers of vinyl chloride are used most frequently in plastisol formulations, copolymer vinyl chloride resins may be used, particularly when the copolymer is able to produce a unique property desired for a specific application. In addition to the vinyl chloride polymer and plasticizer, the plastisol composition frequently contains one or more heat and/or light stabilizers, one or more fillers, and often a colorant. Larger particle size vinyl chloride polymer materials may be used to lower the viscosity of the plastisol composition, or to reduce the cost of the formulation, or to vary the gelation time, or to alter the properties of the fused composition. An addition of a volatile diluent to a plastisol composition will reduce the viscosity of the plastisol. Plastisol compositions to which a volatile diluent has been added usually are referred to as "organosols."
When a plastisol composition is heated, the viscosity of the composition will decrease until the composition reaches a temperature of around 55.degree. C. (which temperature varies somewhat depending on the composition). Thereafter, as the temperature of the composition is raised further, the viscosity of the composition increases rather rapidly until solvation and fusion occur.
Plastisol compositions are used in a variety of processes for manufacturing vinyl chloride polymerproducts. Such processes include rotational castings, slush molding, spread and roll coating, strand coating, cavity molding, and spray coating.